That is a very old VPS version number and they are now in this format, 080405-0 (year, month, day and -0 is the first one of that day if there are more it will be 1-, -2, etc.), which is the latest VPS version.
So you haven't been updating the VPS and no doubt the program is well out of date too, 4.8.1169 is the latest avast version. What is your version ?
So it isn't to surprising your infected. Where does it say your infected (is it after having run an on-demand scan) ?
What Operating System are you using ? is it up to date ?
Your registration may also have expired, complete the
avast! 4 Home Registration form and you will receive an email from register @ avast.com (without the spaces) with your registration key.
I would suggest you Download the latest version of avast
http://www.avast.com/eng/download-avast-home.html and save it to your HDD, somewhere you can find it again. Use that when you reinstall.
Download the avast! Uninstall Utility,
find it here and save it to your HDD.
Now uninstall, reboot, run the uninstall utility, reboot, install the latest version, reboot.
Edit: Hopefully someone else can pick up on this as it is 1:36 a.m. here and I'm about to turn in.
